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1.
J Shoulder Elbow Surg ; 33(7): 1624-1632, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38599456

RESUMEN

BACKGROUND: Antibiotic cement spacers have been widely used in the treatment of joint infections. There are no commercially available antibiotic spacers for the elbow. Instead, they are typically fashioned by the surgeon at the time of surgery using cement alone or a combination of cement with sutures, Steinmann pins, external fixator components, or elbow arthroplasty components. There is no consensus regarding the ideal elbow antibiotic spacer and no previous studies have examined the complications associated with these handmade implants in relation to their unique structural design. METHODS: We retrospectively reviewed 55 patients who had 78 static antibiotic cement spacers implanted between January 1998 and February 2021 as part of a 2-stage treatment plan for infection of an elbow arthroplasty, other elbow surgery, or primary elbow infection. Several antibiotic spacer structures were used during the study period. For analysis purposes, the spacers were classified into linked and unlinked spacers based on whether there was a linking mechanism between the humerus and the ulna. Complications related to these spacers that occurred either during the implantation, between implantation and removal, or during removal were recorded and analyzed from chart review and follow-up x rays. Reoperations due to spacer-related complications were also recorded. RESULTS: Among the 55 patients (78 spacers), there were 23 complications, including 17 minor and 6 major complications. The most common complication of unlinked spacers (intramedullary [IM] dowels, beads and cap spacer) was spacer displacement. Other complications included IM dowel fracture and difficulty locating beads during spacer removal. The major complications of linked cement spacers included two periprosthetic humerus fractures after internal external fixator cement spacers and re-operation due to breakage and displacement of one bushing cement spacer. The major complications of unlinked cement spacers included two reoperations due to IM dowel displacement and one reoperation due to displacement of beads. Among patients who had removal of all components and those with native joints, there was no statistically significant difference between internal external fixator cement spacers and unlinked cement spacers in minor complication rates (30% vs. 16%, P = .16), major complication rates (7% vs. 8%, P = .85) and reoperation rates (0% vs. 8%, P = .12). CONCLUSIONS: Static handmade antibiotic elbow spacers have unique complications related to their structural designs. The most common complication of linked and nonlinked cement spacers were failure of the linking mechanism and displacement, respectively. Surgeons should keep in mind the possible complications of different structures of cement spacers when choosing 1 antibiotic spacer structure over another.


Asunto(s)
Antibacterianos , Cementos para Huesos , Articulación del Codo , Infecciones Relacionadas con Prótesis , Humanos , Estudios Retrospectivos , Antibacterianos/administración & dosificación , Masculino , Femenino , Infecciones Relacionadas con Prótesis/cirugía , Persona de Mediana Edad , Anciano , Articulación del Codo/cirugía , Artroplastia de Reemplazo de Codo/efectos adversos , Reoperación , Adulto , Anciano de 80 o más Años , Prótesis de Codo , Complicaciones Posoperatorias
2.
BMC Oral Health ; 24(1): 534, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724990

RESUMEN

OBJECTIVES: The objectives of this study were to evaluate the cost-effectiveness and cost-benefit of fluoride varnish (FV) interventions for preventing caries in the first permanent molars (FPMs) among children in rural areas in Guangxi, China. METHODS: This study constituted a secondary analysis of data from a randomised controlled trial, analysed from a social perspective. A total of 1,335 children aged 6-8 years in remote rural areas of Guangxi were enrolled in this three-year follow-up controlled study. Children in the experimental group (EG) and the control group (CG) received oral health education and were provided with a toothbrush and toothpaste once every six months. Additionally, FV was applied in the EG. A decision tree model was developed, and single-factor and probabilistic sensitivity analyses were conducted. RESULTS: After three years of intervention, the prevalence of caries in the EG was 50.85%, with an average decayed, missing, and filled teeth (DMFT) index score of 1.12, and that in the CG was 59.04%, with a DMFT index score of 1.36. The total cost of caries intervention and postcaries treatment was 42,719.55 USD for the EG and 46,622.13 USD for the CG. The incremental cost-effectiveness ratio (ICER) of the EG was 25.36 USD per caries prevented, and the cost-benefit ratio (CBR) was 1.74 USD benefits per 1 USD cost. The results of the sensitivity analyses showed that the increase in the average DMFT index score was the largest variable affecting the ICER and CBR. CONCLUSIONS: Compared to oral health education alone, a comprehensive intervention combining FV application with oral health education is more cost-effective and beneficial for preventing caries in the FPMs of children living in economically disadvantaged rural areas. These findings could provide a basis for policy-making and clinical choices to improve children's oral health.


Asunto(s)
Cariostáticos , Análisis Costo-Beneficio , Índice CPO , Caries Dental , Fluoruros Tópicos , Humanos , Caries Dental/prevención & control , Caries Dental/economía , China , Fluoruros Tópicos/uso terapéutico , Fluoruros Tópicos/economía , Niño , Cariostáticos/uso terapéutico , Cariostáticos/economía , Masculino , Femenino , Educación en Salud Dental/economía , Cepillado Dental/economía , Pastas de Dientes/uso terapéutico , Pastas de Dientes/economía , Estudios de Seguimiento , Diente Molar , Árboles de Decisión
3.
BMC Oral Health ; 24(1): 356, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509482

RESUMEN

BACKGROUND: Type 2 diabetes mellitus (T2DM) causes severe bone loss after tooth extraction as a hyperglycemic environment causes aberrant bone homeostasis. Artesunate (ART) is known to possess anti-inflammation and osteogenic properties. However, its osteogenesis property in alveolar bone remains unclear. This study aimed to explore the osteogenic and immunoregulatory effects of artesunate-loaded thermosensitive chitosan hydrogel (ART-loaded TCH) on maxilla tooth extraction in T2DM rats. METHODS: T2DM rats were induced by a high-fat diet and streptozotocin. Different concentrations of ART-loaded TCH were applied in tooth extraction sockets. Bone loss and the expression of osteogenic regulatory factors (OPG, ALP, RANK) were evaluated. The immunoregulatory effects of ART-loaded TCH were observed through detecting the infiltration of T lymphocytes and their cytokines. The underlying mechanisms were explored. RESULTS: Results showed that the 150 mg/ml ART-loaded TCH group significantly ameliorated maxilla bone height and bone mineral density when compared with the T2DM group (p < 0.05). It also improved the expression of OPG, ALP, and RANK. Although the alteration of CD4+ T, CD8+ T, and CD4+:CD8+ T ratio has no significant difference among groups, the release of Th1 and Th2 in the 150 mg/ml ART-loaded TCH group has been significantly regulated than in the T2DM group (p < 0.05). Besides, ART-loaded TCH treatment inhibited the expression of p38 MAPK and ERK1 in T2DM maxilla. CONCLUSIONS: Therefore, the results indicated that 150 mg/ml ART-loaded TCH could be an effective method to prevent bone loss in T2DM tooth extraction rats by modulating the immunoregulation of Th1 and Th2 and the MAPK signaling pathway.


Asunto(s)
Quitosano , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Ratas , Animales , Osteogénesis , Hidrogeles/farmacología , Quitosano/uso terapéutico , Quitosano/farmacología , Artesunato/uso terapéutico , Artesunato/farmacología , Diabetes Mellitus Tipo 2/metabolismo , Maxilar , Linfocitos T/metabolismo , Extracción Dental/métodos
4.
Chembiochem ; 24(21): e202300373, 2023 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-37639367

RESUMEN

Polyethylene terephthalate (PET) is one of the most widely used plastics, and the accumulation of PET poses a great threat to the environment. IsPETase can degrade PET rapidly at moderate temperatures, but its application is greatly limited by the low stability. Herein, molecular dynamics (MD) simulations combined with a sequence alignment strategy were adopted to introduce salt bridges into the flexible region of IsPETase to improve its thermal stability. In the designed variants, the Tm values of IsPETaseI168R/S188D and IsPETaseI168R/S188E were 7.4 and 8.7 °C higher than that of the wild type, respectively. The release of products degraded by IsPETaseI168R/S188E was 4.3 times that of the wild type. Tertiary structure characterization demonstrated that the structure of the variants IsPETaseI168R/S188D and IsPETaseI168R/S188E became more compact. Extensive MD simulations verified that a stable salt bridge was formed between the residue R168 and D186 in IsPETaseI168R/S188D , while in IsPETaseI168R/S188E an R168-D186-E188 salt bridge network was observed. These results confirmed that the proposed computation-based salt bridge design strategy could efficiently generate variants with enhanced thermal stability for the long-term degradation of PET, which would be helpful for the design of enzymes with improved stability.


Asunto(s)
Simulación de Dinámica Molecular , Tereftalatos Polietilenos , Tereftalatos Polietilenos/química , Temperatura , Alineación de Secuencia , Hidrolasas/metabolismo
5.
Macromol Rapid Commun ; 44(1): e2200297, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35621302

RESUMEN

Molecules based on benzimidazolone-dioxazine are known as blue/violet pigments and have been commercialized for decades. However, unfavorable solubility limits the application of these structures as building blocks of conjugated polymers despite their low band gaps. Herein, a series of donor-acceptor conjugated polymers containing soluble benzimidazolone-dioxazine structures as the acceptors and oligothiophene as donors are synthesized and investigated. With increasing numbers of thiophene rings, the steric hindrance diminishes and high molecular weight polymers can be achieved, leading to an improved performance in organic field effect transistor devices. The hole mobility of polymers with three to six thiophene units is in the order of 10-1 cm2 V-1 s -1 . Among all the polymers, polymer P3 with three thiophene units between benzimidazolone-dioxazine structures shows the best hole mobility of 0.4 cm2 V-1 s -1 . Grazing-incidence wide-angle X-ray scattering results reveal that the high mobility of organic field-effect transistors (OFETs) can be accredited by matched donor-acceptor packing in the solid thin films.


Asunto(s)
Vendajes , Bencimidazoles , Polímeros , Tiofenos
6.
J Nanobiotechnology ; 21(1): 241, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37496007

RESUMEN

Wound healing is a common occurrence. However, delayed healing and aberrant scarring result in pathological wound healing. Accordingly, a scarless wound healing remains a significant clinical challenge. In this study, we constructed hyaluronic acid (HA)-modified and verteporfin (VP)-loaded polylactic acid (PLA) nanogels (HA/VP-PLA) to promote scarless wound healing by accelerating wound re-epithelialization and controlling scar formation. Owing to the unique structure of HA incorporating and coating in VP-loaded PLA nanoparticles, HA/VP-PLA could be topically applied on wound to achieve targeted delivery to fibroblasts. Then, HA/VP-PLA released HA and lactic acid (LA) to stimulate the proliferation and migration of fibroblasts, as well as VP to inhibit Yes-associated protein (YAP) expression and nuclear localization to suppress fibrosis. In vitro (skin fibroblasts) and in vivo (rat and rabbit models) experiments strongly suggested that HA/VP-PLA promoted scarless wound healing by accelerating wound re-epithelialization and controlling scar formation. Therefore, our work provides a feasible strategy for scarless wound healing, and the sophisticated HA/VP-PLA exhibit a great potential for clinical applications.


Asunto(s)
Cicatriz , Ácido Hialurónico , Ratas , Animales , Conejos , Cicatriz/tratamiento farmacológico , Cicatriz/prevención & control , Cicatriz/metabolismo , Ácido Hialurónico/química , Repitelización , Nanogeles , Verteporfina , Cicatrización de Heridas , Poliésteres , Piel/metabolismo
7.
J Am Chem Soc ; 144(46): 21267-21277, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36374167

RESUMEN

Tandem semi-stable complementary domains play an important role in life, while the role of these domains in the folding process of nucleic acid molecules has not been systematically studied. Here, we designed a clean model system by synthesizing sequence-defined DNA-OEG copolymers composed of ssDNA fragments with palindromic sequences and orthogonal oligo(tetraethylene glycol) (OEG) linkers. By altering the lengths of DNA units (6-12 nt) and OEG linkers (Xn = 0-4) separately, we systematically studied how stabilities of tandem complementary domains and connecting flexibilities affect the assembly topology. Combining experimental methods and coarse-grained molecular simulation analysis, distributions of multiple assembled conformations (mainly monomers, dimers, and clusters) were characterized. Both results indicated that tandem semi-stable complementary domains tend to form homogeneous closed circular dimers instead of larger clusters due to the synergistic enhancement effect, and the distributions of each conformation highly depend on flexibilities.


Asunto(s)
ADN , Polímeros , ADN de Cadena Simple
8.
Int J Mol Sci ; 23(17)2022 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-36077541

RESUMEN

Understanding interactions between bone morphogenetic proteins (BMPs) and biomaterials is of great significance in preserving the structure and bioactivity of BMPs when utilized in clinical applications. Currently, bone morphogenetic protein-2 (BMP-2) is one of the most important growth factors in bone tissue engineering; however, atomistic interactions between BMP-2 and zinc-substituted hydroxyapatite (Zn-HAP, commonly used in artificial bone implants) have not been well clarified until now. Thus, in this work, the interaction energies, binding/debinding states, and molecular structures of BMP-2 upon a series of Zn-HAP surfaces (Zn-HAPs, 1 at%, 2.5 at%, 5 at%, and 10 at% substitution) were investigated by hybrid molecular dynamics (MD) and steered molecular dynamics (SMD) simulations. Meanwhile, cellular studies including alkaline phosphatase (ALP) activity and reverse transcription-polymerase chain reaction (RT-PCR) assay were performed to verify the theoretical modeling findings. It was found that, compared to pure HAP, Zn-HAPs exhibited a higher binding affinity of BMP-2 at the adsorption process; meanwhile, the detachment of BMP-2 upon Zn-HAPs was more difficult at the desorption process. In addition, molecular structures of BMP-2 could be well stabilized upon Zn-HAPs, especially for Zn10-HAP (with a 10 at% substitution), which showed both the higher stability of cystine-knots and less change in the secondary structures of BMP-2 than those upon HAP. Cellular studies confirmed that higher ALP activity and osteogenic marker gene expression were achieved upon BMP-2/Zn-HAPs than those upon BMP-2/HAP. These findings verified that Zn-HAPs favor the adsorption of BMP-2 and leverage the bioactivity of BMP-2. Together, this work clarified the interaction mechanisms between BMP-2 and Zn-HAPs at the atom level, which could provide new molecular-level insights into the design of BMP-2-loaded biomaterials for bone tissue engineering.


Asunto(s)
Durapatita , Zinc , Adsorción , Materiales Biocompatibles/química , Proteína Morfogenética Ósea 2/metabolismo , Proteínas Morfogenéticas Óseas/química , Durapatita/química , Osteogénesis/genética
9.
Small ; 17(13): e2007391, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33522108

RESUMEN

Breast cancer is the most common malignant disease in women all over the world and its chemotherapy outcome is restricted by multidrug resistance. Here, a nanostructure by functional larotaxel liposomes decorated with guanine-rich quadruplex nucleotide-lipid derivative for treatment of resistant breast cancer is developed. The studies are performed on the resistant breast cancer cells and the cancer-bearing mice. The nucleotide-lipid derivative (DSPE-PEG2000 -C6 -GT28nt) is synthesized by introducing a hydrophobic hexyl linkage between GT-28nt (containing 17 guanines and 11 thymidines) and DSPE-PEG2000 -NHS, and is incorporated on the functional larotaxel liposomes for specific binding with nucleolin receptor on the resistant cancer cells. The studies demonstrate that the liposomes had long circulatory effect, targeted capability, and significant anticancer efficacy in resistant cancer-bearing mice. The studies further reveal their action mechanism, consisting of blocking depolymerization of microtubules, arresting cell cycle, blocking JAK-STAT signaling pathway, and inhibiting activity of antiapoptotic proteins. In conclusion, the functional larotaxel liposomes can be used for effective treatment of drug-resistant breast cancer, and this study also offers a novel targeted nanomedicine based on nucleotide-lipid derivative.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Nanoestructuras , Animales , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Femenino , Guanina , Nucleótidos de Guanina/uso terapéutico , Humanos , Liposomas , Ratones , Taxoides
10.
Plant Cell Rep ; 40(4): 735-751, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33638657

RESUMEN

KEY MESSAGE: GhMYB4 acts as a negative regulator in lignin biosynthesis, which results in alteration of cell wall integrity and activation of cotton defense response. Verticillium wilt of cotton (Gossypium hirsutum) caused by the soil-borne fungus Verticillium dahliae (V. dahliae) represents one of the most important constraints of cotton production worldwide. Mining of the genes involved in disease resistance and illuminating the molecular mechanisms that underlie this resistance is of great importance in cotton breeding programs. Defense-induced lignification in plants is necessary for innate immunity, and there are reports of a correlation between increased lignification and disease resistance. In this study, we present an example in cotton whereby plants with reduced lignin content also exhibit enhanced disease resistance. We identified a negative regulator of lignin synthesis, in cotton encoded in GhMYB4. Overexpression of GhMYB4 in cotton and Arabidopsis enhanced resistance to V. dahliae  with reduced lignin deposition. Moreover, GhMYB4 could bind the promoters of several genes involved in lignin synthesis, such as GhC4H-1, GhC4H-2, Gh4CL-4, and GhCAD-3, and impair their expression. The reduction of lignin content in GhMYB4-overexpressing cotton led to alterations of cell wall integrity (CWI) and released more oligogalacturonides (OGs) which may act as damage-associated molecular patterns (DAMPs) to stimulate plant defense responses. In support of this hypothesis, exogenous application with polygalacturonic acid (PGA) in cotton activated biosynthesis of jasmonic acid (JA) and JA-mediated defense against V. dahliae, similar to that described for cotton plants overexpressing GhMYB4. This study provides a new candidate gene for cotton disease-resistant breeding and an increased understanding of the relationship between lignin synthesis, OG release, and plant immunity.


Asunto(s)
Ascomicetos/patogenicidad , Gossypium/metabolismo , Gossypium/microbiología , Lignina/biosíntesis , Proteínas de Plantas/genética , Acetatos/farmacología , Arabidopsis/genética , Arabidopsis/microbiología , Ciclopentanos/farmacología , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Gossypium/efectos de los fármacos , Gossypium/genética , Lignina/genética , Oxilipinas/farmacología , Pectinas/farmacología , Filogenia , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Inmunidad de la Planta , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Ácido Salicílico/farmacología , Factores de Transcripción/genética
11.
Int J Mol Sci ; 22(14)2021 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-34298988

RESUMEN

This study evaluated the biocompatibility and biological performance of novel additive-manufactured bioabsorbable iron-based porous suture anchors (iron_SAs). Two types of bioabsorbable iron_SAs, with double- and triple-helical structures (iron_SA_2_helix and iron_SA_3_helix, respectively), were compared with the synthetic polymer-based bioabsorbable suture anchor (polymer_SAs). An in vitro mechanical test, MTT assay, and scanning electron microscope (SEM) analysis were performed. An in vivo animal study was also performed. The three types of suture anchors were randomly implanted in the outer cortex of the lateral femoral condyle. The ultimate in vitro pullout strength of the iron_SA_3_helix group was significantly higher than the iron_SA_2_helix and polymer_SA groups. The MTT assay findings demonstrated no significant cytotoxicity, and the SEM analysis showed cells attachment on implant surface. The ultimate failure load of the iron_SA_3_helix group was significantly higher than that of the polymer_SA group. The micro-CT analysis indicated the iron_SA_3_helix group showed a higher bone volume fraction (BV/TV) after surgery. Moreover, both iron SAs underwent degradation with time. Iron_SAs with triple-helical threads and a porous structure demonstrated better mechanical strength and high biocompatibility after short-term implantation. The combined advantages of the mechanical superiority of the iron metal and the possibility of absorption after implantation make the iron_SA a suitable candidate for further development.


Asunto(s)
Implantes Absorbibles , Materiales Biocompatibles , Anclas para Sutura , Alanina Transaminasa/sangre , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/toxicidad , Fenómenos Biomecánicos , Nitrógeno de la Urea Sanguínea , Fosfatos de Calcio/química , Fosfatos de Calcio/toxicidad , Sulfato de Calcio/administración & dosificación , Sulfato de Calcio/química , Sulfato de Calcio/toxicidad , Creatinina/sangre , Diseño de Equipo , Fémur/diagnóstico por imagen , Fémur/ultraestructura , Hierro , Rayos Láser , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Estructura Molecular , Oseointegración , Polímeros/química , Polímeros/toxicidad , Porosidad , Conejos , Distribución Aleatoria , Resistencia a la Tracción , Vísceras , Microtomografía por Rayos X
12.
Ann Bot ; 121(2): 255-266, 2018 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-29267935

RESUMEN

Background and Aims: To understand the link between species diversity and phenotype developmental evolution is an important issue in evolutionary biology. Yarrows in the genus Achillea (Asteraceae) show a great diversity in leaf serrate or pinnate dissection patterns. In Arabidopsis thaliana, the development of leaf serration requires the activity of the transcription factor CUC2. Does this regulator also work for leaf dissections of the Asteraceae plants? If so, how do the conserved regulatory 'tools' work differently to produce diverse leaf forms? Methods: Seedling leaf morphology was observed, and morphogenesis of leaf serration or lobes was examined by scanning electron microscopy (SEM). NAM genes, orthologues of arabidopsis CUC2, were isolated from A. acuminata with serrate leaves and A. asiatica with three-pinnatisect leaves, respectively. By means of whole-mount in situ mRNA hybridization and two quantitative gene expression assays, the droplet digital PCR (ddPCR) and quantitative real-time PCR (qPCR), expression patterns of the NAM genes during leaf dissection development were checked in both species for comparison. Key Results: For both species, the development of leaf dissection initiated when a leaf blade was about 300-400 µm long. In A. acuminata, in situ hybridization showed NAM expression signals at leaf margins where teeth are growing, or later on, in the sinuses of the teeth, whilst in A. asiatica, hybridization signals appear not only on leaf margins but further on the margins of leaf lobes. Both ddPCR and qPCR revealed a continuous decline of AacNAM expression from the early to the late developmental stages of a single leaf of A. acuminata, whereas a relatively long maintenance and fluctuation of AasNAM expression was seen in a leaf of A. asiatica. Conclusions: Differential spatiotemporal patterns of NAM expression were found between the two yarrow species during development of leaf dissection. This study provides the first evidence for NAM activity in the development of leaf dissection of the Asteraceae plants, and demonstrates that leaf form diversity is correlated to the altered NAM expression dynamic.


Asunto(s)
Achillea/anatomía & histología , Genes de Plantas/fisiología , Hojas de la Planta/anatomía & histología , Achillea/genética , Achillea/ultraestructura , Paseo de Cromosoma , Regulación de la Expresión Génica de las Plantas , Genes de Plantas/genética , Hibridación in Situ , Microscopía Electrónica de Rastreo , Filogenia , Hojas de la Planta/genética , Hojas de la Planta/ultraestructura , Proteínas de Plantas/genética , Proteínas de Plantas/fisiología , Reacción en Cadena en Tiempo Real de la Polimerasa , Plantones/anatomía & histología , Plantones/ultraestructura , Factores de Transcripción/genética , Factores de Transcripción/fisiología
13.
J Exp Bot ; 68(18): 5129-5136, 2017 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-28992345

RESUMEN

Lignin is an important component of many plant secondary cell walls. In the fruit of loquat (Eriobotrya japonica), lignification of cell walls in the fleshy tissue occurs when fruit are subjected to low-temperature storage, which is commonly used to avoid the rapid senescence that occurs at room temperature. In this study, two NAC domain genes, EjNAC3 and EjNAC4, were isolated and shown to be significantly induced at 0 °C, which was concomitant with an increase in the fruit lignification index. Lignification and expression of both EjNAC3 and EjNAC4 were inhibited by low-temperature conditioning and by heat treatment. In addition, EjNAC3 trans-activated the lignin biosynthesis-related EjCAD-like promoter, which was measured using a dual-luciferase assay. Further analysis with yeast one-hybrid and electrophoretic mobility shift assays indicated that EjNAC3 could physically bind to the promoter of the EjCAD-like gene. Thus, EjNAC3 is a direct regulator of loquat chilling-induced lignification, via regulations of EjCAD-like.


Asunto(s)
Eriobotrya/genética , Regulación de la Expresión Génica de las Plantas , Lignina/metabolismo , Factores de Transcripción/metabolismo , Pared Celular/metabolismo , Frío , Ensayo de Cambio de Movilidad Electroforética , Eriobotrya/fisiología , Frutas/genética , Frutas/fisiología , Redes Reguladoras de Genes , Genes Reporteros , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiones Promotoras Genéticas/genética , Factores de Transcripción/genética , Técnicas del Sistema de Dos Híbridos
14.
Plant Cell Environ ; 39(8): 1780-9, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27006258

RESUMEN

Transcriptional regulatory mechanisms underlying lignin metabolism have been widely studied in model plants and woody trees, as well as fruit, such as loquat (Eriobotrya japonica). Unlike the well-known NAC, MYB and AP2/ERF transcription factors, the roles of heat shock factors (HSFs) in lignin regulation have been rarely reported. Two treatments (heat treatment, HT; low temperature conditioning, LTC) were applied to alleviate low temperature-induced lignification in loquat fruit. Gene expression analysis indicated that EjHSF1 transcript abundance, in parallel with heat shock protein genes (EjHsp), was induced by HT, while expression of EjHSF3 was repressed by LTC. Using dual-luciferase assays, EjHSF1 and EjHSF3 trans-activated the promoters of EjHsp genes and lignin biosynthesis-related genes, respectively. Thus, two distinct regulatory mechanisms of EjHSF transcription factors in chilling injury-induced fruit lignification are proposed: EjHSF1 transcriptionally regulated EjHsp genes are involved in chilling tolerance, while EjHSF3 transcriptionally regulated lignin biosynthesis. Furthermore, the relations between EjHSF3 and previously characterized fruit lignification regulators, including EjAP2-1, EjMYB1 and EjMYB2, were also investigated. Yeast-two hybrid (Y2H) and biomolecular fluorescence complementation (BiFC) assays demonstrated protein-protein interaction between EjHSF3 and EjAP2-1. Thus, the involvement of EjHSF3 in fruit lignification is via both lignin biosynthetic genes and the regulator, EjAP2-1.


Asunto(s)
Eriobotrya/metabolismo , Frutas/metabolismo , Factores de Transcripción del Choque Térmico/metabolismo , Proteínas de Choque Térmico/metabolismo , Lignina/biosíntesis , Frío , Eriobotrya/genética , Regulación de la Expresión Génica de las Plantas , Factores de Transcripción del Choque Térmico/genética , Proteínas de Choque Térmico/genética
15.
Artif Organs ; 40(11): 1062-1070, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26814438

RESUMEN

Clinical implantation of clavicle hook plates is often used as a treatment for acromioclavicular joint dislocation. However, it is not uncommon to find patients that have developed acromion osteolysis or had peri-implant fracture after hook plate fixation. With the aim of preventing complications or fixation failure caused by implantation of inappropriate clavicle hook plates, the present study investigated the biomechanics of clavicle hook plates made of different materials and with different hook depths in treating acromioclavicular joint dislocation, using finite element analysis (FEA). This study established four parts using computer models: the clavicle, acromion, clavicle hook plate, and screws, and these established models were used for FEA. Moreover, implantations of clavicle hook plates made of different materials (stainless steel and titanium alloy) and with different depths (12, 15, and 18 mm) in patients with acromioclavicular joint dislocation were simulated in the biomechanical analysis. The results indicate that deeper implantation of the clavicle hook plate reduces stress on the clavicle, and also reduces the force applied to the acromion by the clavicle hook plate. Even though a clavicle hook plate made of titanium alloy (a material with a lower Young's modulus) reduces the force applied to the acromion by the clavicle hook plate, slightly higher stress on the clavicle may occur. The results obtained in this study provide a better reference for orthopedic surgeons in choosing different clavicle hook plates for surgery.


Asunto(s)
Articulación Acromioclavicular/cirugía , Placas Óseas , Clavícula/cirugía , Análisis de Elementos Finitos , Fijación Interna de Fracturas/instrumentación , Luxaciones Articulares/cirugía , Aleaciones , Fenómenos Biomecánicos , Simulación por Computador , Humanos , Osteólisis/prevención & control , Fracturas Periprotésicas/prevención & control , Complicaciones Posoperatorias/prevención & control , Acero Inoxidable , Titanio , Resultado del Tratamiento
16.
Plant Biotechnol J ; 13(9): 1325-34, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25778106

RESUMEN

Lignin biosynthesis is regulated by many transcription factors, such as those of the MYB and NAC families. However, the roles of AP2/ERF transcription factors in lignin biosynthesis have been rarely investigated. Eighteen EjAP2/ERF genes were isolated from loquat fruit (Eriobotrya japonica), which undergoes postharvest lignification during low temperature storage. Among these, expression of EjAP2-1, a transcriptional repressor, was negatively correlated with fruit lignification. The dual-luciferase assay indicated that EjAP2-1 could trans-repress activities of promoters of lignin biosynthesis genes from both Arabidopsis and loquat. However, EjAP2-1 did not interact with the target promoters (Ej4CL1). Yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays indicated protein-protein interactions between EjAP2-1 and lignin biosynthesis-related EjMYB1 and EjMYB2. Furthermore, repression effects on the Ej4CL1 promoter were observed with the combination of EjAP2-1 and EjMYB1 or EjMYB2, while EjAP2-1 with the EAR motif mutated (mEjAP2-1) lost such repression, although mEjAP2-1 still interacted with EjMYB protein. Based on these results, it is proposed that EjAP2-1 is an indirect transcriptional repressor on lignin biosynthesis, and the repression effects were manifested by EAR motifs and were conducted via protein-protein interaction with EjMYBs.


Asunto(s)
Frío/efectos adversos , Eriobotrya/genética , Frutas/genética , Regulación de la Expresión Génica de las Plantas/genética , Genes de Plantas/genética , Lignina/metabolismo , Proteínas de Plantas/genética , Factores de Transcripción/genética , Eriobotrya/metabolismo , Frutas/metabolismo , Genes de Plantas/fisiología , Redes y Vías Metabólicas/genética , Redes y Vías Metabólicas/fisiología , Filogenia , Proteínas de Plantas/fisiología , Factores de Transcripción/fisiología
17.
Eur Spine J ; 24(10): 2182-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25940568

RESUMEN

PURPOSE: Giant cell tumor of the sacrum is usually silent in initial stages and not diagnosed until achieving a large size. Intralesional curettage of the tumor has lower risk of neurological damage but is with high recurrence rate. Zoledronic acid-loaded cement was demonstrated to have cytotoxic effect on the cell line of giant cell tumor. This study evaluate if zoledronic acid-loaded bone cement would reduce the recurrence rate of sacral giant cell tumor after intralesional curettage. METHODS: Four patients were diagnosed as sacral giant cell tumor and received intralesional curettage with placement of zoledronic acid-loaded bone cement for adjuvant local control. The clinical records including tumor location, tumor size, complication, follow-up status, and functional outcome were analyzed retrospectively. RESULTS: All four patients presented with cauda equina syndrome before surgery with mean tumor volume of 472.8 cm(3). With placement of zoledronic acid-loaded cement, no local recurrence was observed during the mean follow-up period of 28 months. All patients were found to have new bone regeneration on radiograph. All patients suffering from cauda equina syndrome were recovered. CONCLUSIONS: We suggested that placement of zoledronic acid-loaded bone cement was an effective adjuvant therapy for sacral giant cell tumor following intralesional curettage.


Asunto(s)
Cementos para Huesos/uso terapéutico , Conservadores de la Densidad Ósea , Neoplasias Óseas/terapia , Difosfonatos , Tumor Óseo de Células Gigantes/terapia , Imidazoles , Polirradiculopatía/cirugía , Sacro/cirugía , Adolescente , Adulto , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/uso terapéutico , Estudios de Cohortes , Terapia Combinada , Legrado , Difosfonatos/administración & dosificación , Difosfonatos/uso terapéutico , Femenino , Humanos , Imidazoles/administración & dosificación , Imidazoles/uso terapéutico , Masculino , Estudios Retrospectivos , Adulto Joven , Ácido Zoledrónico
18.
Am J Orthod Dentofacial Orthop ; 148(6): 1043-53, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26672711

RESUMEN

This case report describes the orthodontic camouflage treatment for a 16-year-old Chinese girl with a Class III malocclusion. The treatment included extractions of the mandibular second molars, fixed appliance therapy, and miniscrew-aided mandibular arch distalization. Pretreatment, posttreatment, and 2-year follow-up records are shown. The anterior negative overjet and the Class III molar and canine relationships were corrected. The patient's facial profile was greatly improved. The mandibular third molars erupted into the second molar spaces, with acceptable intercuspation with the maxillary dentition.


Asunto(s)
Tornillos Óseos , Maloclusión de Angle Clase III/terapia , Métodos de Anclaje en Ortodoncia/instrumentación , Diseño de Aparato Ortodóncico , Técnicas de Movimiento Dental/instrumentación , Adolescente , Cefalometría/métodos , Diente Canino/patología , Arco Dental/patología , Femenino , Estudios de Seguimiento , Humanos , Incisivo/patología , Mandíbula/patología , Diente Molar/patología , Sobremordida/terapia , Planificación de Atención al Paciente , Prognatismo/terapia , Resultado del Tratamiento
19.
J Exp Bot ; 65(15): 4349-59, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24860186

RESUMEN

Lignin biosynthesis and its transcriptional regulatory networks have been studied in model plants and woody trees. However, lignification also occurs in some fleshy fruit and has rarely been considered in this way. Loquat ( Eriobotrya japonica ) is one such convenient tissue for exploring the transcription factors involved in regulating fruit flesh lignification. Firmness and lignin content of 'Luoyangqing' loquat were fund to increase during low-temperature storage as a typical symptom of chilling injury, while heat treatment (HT) and low-temperature conditioning (LTC) effectively alleviated them. Two novel EjMYB genes, EjMYB1 and EjMYB2, were isolated and were found to be localized in the nucleus. These genes responded differently to low temperature, with EjMYB1 induced and EjMYB2 inhibited at 0 °C. They also showed different temperature responses under HT and LTC conditions, and may be responsible for different regulation of flesh lignification at the transcriptional level. Transactivation assays indicated that EjMYB1 and EjMYB2 are a transcriptional activator and repressor, respectively. EjMYB1 activated promoters of both Arabidopsis and loquat lignin biosynthesis genes, while EjMYB2 countered the inductive effects of EjMYB1. This finding was also supported by transient overexpression in tobacco. Regulation of lignification by EjMYB1 and EjMYB2 is likely to be achieved via their competitive interaction with AC elements in the promoter region of lignin biosynthesis genes such as Ej4CL1.


Asunto(s)
Eriobotrya/metabolismo , Frutas/metabolismo , Lignina/biosíntesis , Factores de Transcripción/metabolismo , Arabidopsis/genética , Frío , Eriobotrya/genética , Regulación de la Expresión Génica de las Plantas , Regiones Promotoras Genéticas , Propanoles/metabolismo , Nicotiana , Técnicas del Sistema de Dos Híbridos
20.
Microsurgery ; 34(5): 409-12, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24442986

RESUMEN

We presented a patient who experienced the anterolateral thigh (ALT) flap failure but the reconstruction was successfully salvaged by harvesting a second ALT flap from the same donor site 2 days after the first reconstruction. A 47-year-old man received cancer ablation for right mouth floor squamous cell carcinoma. The resultant defect was planned to be reconstructed with the ALT flap. During the flap dissection, we identified three proximal cutaneous perforators originating from the transverse branch of the lateral circumflex femoral artery (t-LCFA) and two distal cutaneous perforators originating from the descending branch (d-LCFA). We harvested a skin flap based on the distal two perforators and divided the d-LCFA just distal to the bifurcation of the d-LCFA and the t-LCFA. Unfortunately, the ALT flap showed venous congestion on postoperative day 2 and eventually failed. We harvested a second ALT flap from the same donor site based on the previously preserved perforators. The recovery course was smooth thereafter. We believe that the harvest of a second ALT flap from the same donor site may be an option, to avoid other donor site violation, in some patients who experienced the first flap loss. © 2014 Wiley Periodicals, Inc. Microsurgery 34:409-412, 2014.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Neoplasias de Cabeza y Cuello/cirugía , Neoplasias de la Boca/cirugía , Colgajo Perforante , Humanos , Masculino , Persona de Mediana Edad , Procedimientos de Cirugía Plástica/métodos , Terapia Recuperativa , Carcinoma de Células Escamosas de Cabeza y Cuello , Recolección de Tejidos y Órganos , Insuficiencia del Tratamiento
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